Study on risk assessment models for the aggregation of vehicles transporting hazardous chemicals

Aggregation of vehicles transporting hazardous chemicals is part of a complex system of hazardous chemical transportation with frequent accidents that threaten public safety. In order to avoid catastrophic consequences in the vehicle aggregation areas, dynamic risk assessment models have been studied in this paper. The macro quantitative risk assessment (M-QRA) model determines the accident probability through the probability of leakage and the probability of induced secondary accidents and takes into account the domino effect to determine the risk in conjunction with the consequence of pool fire, but some data are not readily available. Therefore, in order to accurately assess the risk in case of incomplete data, a rapid quantitative risk assessment (R-QRA) model considering the number of vehicles and the critical mass of hazardous chemicals was developed. In this paper, the M-QRA and R-QRA model were used to calculate the real-time risk of aggregation of vehicles transporting hazardous chemicals respectively, and the two models were compared in terms of calculation accuracy and assessment efficiency. The results show that the risks obtained from the two models are basically consistent, but the R-QRA model is faster in calculation, which is of great practical significance for actual engineering applications and helps safety management.